An avalanche killed six skiers in the Italian Alps on Saturday, making it one of the deadliest to hit the area in many years, a fire department spokeswoman said.

Of the six bodies recovered, four were Italian citizens and two others have yet to be identified, the spokeswoman said. An injured Austrian woman was being treated in hospital in the town of Brunico.

Two others caught in the snowslide were able to free themselves without injury. Three helicopters, specially trained dogs and more than 70 alpine rescuers and fire fighters were continuing to search for bodies.

"We know there were several groups in the same area, which is why we are still searching," the spokeswoman said. "We don't know yet if everyone has been accounted for."

The avalanche took place during the morning at more than 3,000 metres (9,800 ft) on Mount Nevoso, or "Snowy Mountain", in South Tyrol, near the Austrian border. Conditions were sunny and windy after heavy snowfall in recent weeks, a local police official said.

The skiers were climbing to the mountain's summit and were planning to ski down. Exactly how the avalanche was caused is still unknown, the spokeswoman said.

There was a "marked" risk of avalanche of 3 in the area at the time, on a scale where 5 indicates a strong risk, Italian media reported.